Battery charger



FIG. 1 is a perspective view of a design for a battery charger of the present invention;

FIG. 2 is a front view thereof;

FIG. 3 is a back view thereof;

FIG. 4 is a top view thereof;

FIG. 5 is a bottom thereof;

FIG. 6 is a right side view thereof; and,

FIG. 7 is a left side view thereof.

The broken lines shown in the drawings are included for the purpose of illustrating environmental structure and form no part of the claimed design. 

CLAIM The ornamental design for a battery charger, as shown and described above. 